Odd annoyance-
If I arrow down too quickly after "ON ", I see the first suggestion for a join condition select, then quickly deselects itself. If I wait a 2 second count or so before hitting the arrow down button, It doesn't deselect.

By default, there is a 300 millisecond delay before the suggestion is triggered.
Could you try decreasing this delay and see if that helps?
You can set it through SQL Prompt 5 > Options > Behaviour > Triggering Behaviour